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Diffstat (limited to 'fs/nilfs2/segment.h')
| -rw-r--r-- | fs/nilfs2/segment.h | 246 |
1 files changed, 246 insertions, 0 deletions
diff --git a/fs/nilfs2/segment.h b/fs/nilfs2/segment.h new file mode 100644 index 00000000000..615654b8c32 --- /dev/null +++ b/fs/nilfs2/segment.h @@ -0,0 +1,246 @@ +/* + * segment.h - NILFS Segment constructor prototypes and definitions + * + * Copyright (C) 2005-2008 Nippon Telegraph and Telephone Corporation. + * + * This program is free software; you can redistribute it and/or modify + * it under the terms of the GNU General Public License as published by + * the Free Software Foundation; either version 2 of the License, or + * (at your option) any later version. + * + * This program is distributed in the hope that it will be useful, + * but WITHOUT ANY WARRANTY; without even the implied warranty of + * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the + * GNU General Public License for more details. + * + * You should have received a copy of the GNU General Public License + * along with this program; if not, write to the Free Software + * Foundation, Inc., 51 Franklin St, Fifth Floor, Boston, MA 02110-1301 USA + * + * Written by Ryusuke Konishi <ryusuke@osrg.net> + * + */ +#ifndef _NILFS_SEGMENT_H +#define _NILFS_SEGMENT_H + +#include <linux/types.h> +#include <linux/fs.h> +#include <linux/buffer_head.h> +#include <linux/nilfs2_fs.h> +#include "sb.h" + +/** + * struct nilfs_recovery_info - Recovery infomation + * @ri_need_recovery: Recovery status + * @ri_super_root: Block number of the last super root + * @ri_ri_cno: Number of the last checkpoint + * @ri_lsegs_start: Region for roll-forwarding (start block number) + * @ri_lsegs_end: Region for roll-forwarding (end block number) + * @ri_lseg_start_seq: Sequence value of the segment at ri_lsegs_start + * @ri_used_segments: List of segments to be mark active + * @ri_pseg_start: Block number of the last partial segment + * @ri_seq: Sequence number on the last partial segment + * @ri_segnum: Segment number on the last partial segment + * @ri_nextnum: Next segment number on the last partial segment + */ +struct nilfs_recovery_info { + int ri_need_recovery; + sector_t ri_super_root; + __u64 ri_cno; + + sector_t ri_lsegs_start; + sector_t ri_lsegs_end; + u64 ri_lsegs_start_seq; + struct list_head ri_used_segments; + sector_t ri_pseg_start; + u64 ri_seq; + __u64 ri_segnum; + __u64 ri_nextnum; +}; + +/* ri_need_recovery */ +#define NILFS_RECOVERY_SR_UPDATED 1 /* The super root was updated */ +#define NILFS_RECOVERY_ROLLFORWARD_DONE 2 /* Rollforward was carried out */ + +/** + * struct nilfs_cstage - Context of collection stage + * @scnt: Stage count + * @flags: State flags + * @dirty_file_ptr: Pointer on dirty_files list, or inode of a target file + * @gc_inode_ptr: Pointer on the list of gc-inodes + */ +struct nilfs_cstage { + int scnt; + unsigned flags; + struct nilfs_inode_info *dirty_file_ptr; + struct nilfs_inode_info *gc_inode_ptr; +}; + +struct nilfs_segment_buffer; + +struct nilfs_segsum_pointer { + struct buffer_head *bh; + unsigned offset; /* offset in bytes */ +}; + +/** + * struct nilfs_sc_info - Segment constructor information + * @sc_super: Back pointer to super_block struct + * @sc_sbi: Back pointer to nilfs_sb_info struct + * @sc_nblk_inc: Block count of current generation + * @sc_dirty_files: List of files to be written + * @sc_gc_inodes: List of GC inodes having blocks to be written + * @sc_active_segments: List of active segments that were already written out + * @sc_cleaning_segments: List of segments to be freed through construction + * @sc_copied_buffers: List of copied buffers (buffer heads) to freeze data + * @sc_segbufs: List of segment buffers + * @sc_segbuf_nblocks: Number of available blocks in segment buffers. + * @sc_curseg: Current segment buffer + * @sc_super_root: Pointer to the super root buffer + * @sc_stage: Collection stage + * @sc_finfo_ptr: pointer to the current finfo struct in the segment summary + * @sc_binfo_ptr: pointer to the current binfo struct in the segment summary + * @sc_blk_cnt: Block count of a file + * @sc_datablk_cnt: Data block count of a file + * @sc_nblk_this_inc: Number of blocks included in the current logical segment + * @sc_seg_ctime: Creation time + * @sc_flags: Internal flags + * @sc_sketch_inode: Inode of the sketch file + * @sc_state_lock: spinlock for sc_state and so on + * @sc_state: Segctord state flags + * @sc_flush_request: inode bitmap of metadata files to be flushed + * @sc_wait_request: Client request queue + * @sc_wait_daemon: Daemon wait queue + * @sc_wait_task: Start/end wait queue to control segctord task + * @sc_seq_request: Request counter + * @sc_seq_done: Completion counter + * @sc_sync: Request of explicit sync operation + * @sc_interval: Timeout value of background construction + * @sc_mjcp_freq: Frequency of creating checkpoints + * @sc_lseg_stime: Start time of the latest logical segment + * @sc_watermark: Watermark for the number of dirty buffers + * @sc_timer: Timer for segctord + * @sc_task: current thread of segctord + */ +struct nilfs_sc_info { + struct super_block *sc_super; + struct nilfs_sb_info *sc_sbi; + + unsigned long sc_nblk_inc; + + struct list_head sc_dirty_files; + struct list_head sc_gc_inodes; + struct list_head sc_active_segments; + struct list_head sc_cleaning_segments; + struct list_head sc_copied_buffers; + + /* Segment buffers */ + struct list_head sc_segbufs; + unsigned long sc_segbuf_nblocks; + struct nilfs_segment_buffer *sc_curseg; + struct buffer_head *sc_super_root; + + struct nilfs_cstage sc_stage; + + struct nilfs_segsum_pointer sc_finfo_ptr; + struct nilfs_segsum_pointer sc_binfo_ptr; + unsigned long sc_blk_cnt; + unsigned long sc_datablk_cnt; + unsigned long sc_nblk_this_inc; + time_t sc_seg_ctime; + + unsigned long sc_flags; + + /* + * Pointer to an inode of the sketch. + * This pointer is kept only while it contains data. + * We protect it with a semaphore of the segment constructor. + */ + struct inode *sc_sketch_inode; + + spinlock_t sc_state_lock; + unsigned long sc_state; + unsigned long sc_flush_request; + + wait_queue_head_t sc_wait_request; + wait_queue_head_t sc_wait_daemon; + wait_queue_head_t sc_wait_task; + + __u32 sc_seq_request; + __u32 sc_seq_done; + + int sc_sync; + unsigned long sc_interval; + unsigned long sc_mjcp_freq; + unsigned long sc_lseg_stime; /* in 1/HZ seconds */ + unsigned long sc_watermark; + + struct timer_list *sc_timer; + struct task_struct *sc_task; +}; + +/* sc_flags */ +enum { + NILFS_SC_DIRTY, /* One or more dirty meta-data blocks exist */ + NILFS_SC_UNCLOSED, /* Logical segment is not closed */ + NILFS_SC_SUPER_ROOT, /* The latest segment has a super root */ + NILFS_SC_PRIOR_FLUSH, /* Requesting immediate flush without making a + checkpoint */ +}; + +/* sc_state */ +#define NILFS_SEGCTOR_QUIT 0x0001 /* segctord is being destroyed */ +#define NILFS_SEGCTOR_COMMIT 0x0004 /* committed transaction exists */ + +/* + * Constant parameters + */ +#define NILFS_SC_CLEANUP_RETRY 3 /* Retry count of construction when + destroying segctord */ + +/* + * Default values of timeout, in seconds. + */ +#define NILFS_SC_DEFAULT_TIMEOUT 5 /* Timeout value of dirty blocks. + It triggers construction of a + logical segment with a super root */ +#define NILFS_SC_DEFAULT_SR_FREQ 30 /* Maximum frequency of super root + creation */ +#define NILFS_SC_DEFAULT_SB_FREQ 30 /* Minimum interval of periodical + update of superblock (reserved) */ + +/* + * The default threshold amount of data, in block counts. + */ +#define NILFS_SC_DEFAULT_WATERMARK 3600 + + +/* segment.c */ +extern int nilfs_init_transaction_cache(void); +extern void nilfs_destroy_transaction_cache(void); +extern void nilfs_relax_pressure_in_lock(struct super_block *); + +extern int nilfs_construct_segment(struct super_block *); +extern int nilfs_construct_dsync_segment(struct super_block *, + struct inode *); +extern void nilfs_flush_segment(struct super_block *, ino_t); +extern int nilfs_clean_segments(struct super_block *, void __user *); + +extern int nilfs_segctor_add_segments_to_be_freed(struct nilfs_sc_info *, + __u64 *, size_t); +extern void nilfs_segctor_clear_segments_to_be_freed(struct nilfs_sc_info *); + +extern int nilfs_attach_segment_constructor(struct nilfs_sb_info *, + struct nilfs_recovery_info *); +extern void nilfs_detach_segment_constructor(struct nilfs_sb_info *); + +/* recovery.c */ +extern int nilfs_read_super_root_block(struct super_block *, sector_t, + struct buffer_head **, int); +extern int nilfs_search_super_root(struct the_nilfs *, struct nilfs_sb_info *, + struct nilfs_recovery_info *); +extern int nilfs_recover_logical_segments(struct the_nilfs *, + struct nilfs_sb_info *, + struct nilfs_recovery_info *); + +#endif /* _NILFS_SEGMENT_H */ |